A Study to Evaluate the Efficacy and Safety of Erenumab (AMG 334) in Chronic Migraine Prevention

Inclusion Criteria

• •History of at least 5 attacks of migraine without aura and/or migraine with visual sensory, speech and/or language, retinal or brainstem aura.
• •History of ≥ 15 headache days per month of which ≥ 8 headache days were assessed by the subject as migraine day.
• •≥ 4 distinct headache episodes, each lasting ≥ 4 hours OR if shorter, associated with use of a triptan or ergot-derivative on the same calendar day based on the eDiary calculations.
• •Demonstrated at least 80% compliance with the eDiary.